Sir Keir Starmer has appointed Sir Tony Blair’s former chief of staff Jonathan Powell as National Security Adviser.

Mr Powell will take over from Sir Tim Barrow in the role based in 10 Downing Street, the Cabinet Office said.

The Prime Minister said his experience in helping to negotiate the Good Friday Agreement and working on “some of the world’s most complex conflicts” meant he was “uniquely qualified” to advise the Government on global challenges.

“Jonathan has devoted his career to protecting the interests of the country, having served for 17 years as a diplomat in the Foreign Office and 10 years as chief of staff in No 10, and I am delighted to appoint him to this important role,” Sir Keir said.

Jonathan Powell, right, was Sir Tony Blair’s former chief of staff (Niall Carson/PA)

“Together with his experience helping to negotiate the Belfast (Good Friday) Agreement and work on some of the world’s most complex conflicts, he is uniquely qualified to advise the Government on tackling the challenges ahead and engage with counterparts across the globe to protect and advance UK interests.

“I would also like to thank Sir Tim Barrow for his service and the support and advice he has given me. He has helped steer the national security community through some of the most challenging times in recent history, demonstrating throughout his outstanding commitment to public service and to the safety and security of this country. I’ve no doubt he will continue to play a positive role on these issues in the future.”

Mr Powell said: “I am honoured to have been appointed as the National Security Adviser to the Prime Minister. This is a hugely important role at a time where national security, international relations, and domestic policies are so interconnected.

“As the Prime Minister has set out, national security is at the heart of this country’s response to the many challenges we face and having an integrated response will be crucial to our success. I look forward to advising the Prime Minister and working closely with ministers and officials in this new role.”